The present invention relates to a golf clubhead and a manufacturing method therefor, and more particularly to an internal structure of the hosel portion of the golf club head which is capable of providing greater flexibility in the designing of the golf clubhead.
In recent years, there is a tendency for the wood-type golf clubs to increase the size or volume of the clubhead. Although the volume of the clubhead is increased, the weight of the clubhead should not be increased. In designing such a wood-type golf clubhead, a target weight and target volume of the clubhead are usually first given, and the position of the center of gravity of the clubhead, which greatly affects the position of the sweet spot, moment of inertia, performance, feel and the like, must be determined relative to the club shaft. In a conventional wood-type metal head whose volume is not so large, an extension of the hosel which is usually provided in the clubhead is formed as a protuberance extending along the inside of the clubhead as shown in FIGS. 13a and 13b. In this structure, if the head volume is increased and as a result it becomes necessary to shift the hosel portion towards the center of the clubhead, the protuberance becomes large and the weight is increased in this part. As a result, it becomes very difficult to adjust every design parameter to the desired target value. To satisfy one parameter, it becomes necessary to sacrifice another parameter. For example, the head volume is decreased to achieve the position of the center of gravity. Thus, it becomes very difficult to freely design such a clubhead.